Objective To explore the construction and biocompatibility in vitro evaluation of the electrospun-graphene (Gr)/silk fibroin (SF) nanofilms. Methods The electrostatic spinning solution was prepared by dissolving SF and different mass ratio (0, 5%, 10%, 15%, and 20%) of Gr in formic acid solution. The hydrophilia and hydrophobic was analyzed by testing the static contact angle of electrostatic spinning solution of different mass ratio of Gr. Gr-SF nanofilms with different mass ratio (0, 5%, 10%, 15%, and 20%, as groups A, B, C, D, and E, respectively) were constructed by electrospinning technology. The structure of nanofilms were observed by optical microscope and scanning electron microscope; electrochemical performance of nanofilms were detected by cyclic voltammetry at electrochemical workstation; the porosity of nanofilms were measured by n-hexane substitution method, and the permeability were observed; L929 cells were used to evaluate the cytotoxicity of nanofilms in vitro at 1, 4, and 7 days after culture. The primary Sprague Dawley rats’ Schwann cells were co-cultured with different Gr-SF nanofilms of 5 groups for 3 days, the morphology and distribution of Schwann cells were identified by toluidine blue staining, the cell adhesion of Schwann cells were determined by cell counting kit 8 (CCK-8) method, the proliferation of Schwann cells were detected by EdU/Hoechst33342 staining. Results The static contact angle measurement confirmed that the hydrophilia of Gr-SF electrospinning solution was decreased by increasing the mass ratio of Gr. Light microscope and scanning electron microscopy showed that Gr-SF nanofilms had nanofiber structure, Gr particles could be dispersed uniformly in the membrane, and the increasing of mass ratio of Gr could lead to the aggregation of particles. The porosity measurement showed that the Gr-SF nanofilms had high porosity (>65%). With the increasing of mass ratio of Gr, the porosity and conductivity of Gr-SF nanofilm increased gradually, the value in the group A was significantly lower than those in groups C, D, and E (P<0.05). In vitro L929 cells cytotoxicity test showed that all the Gr-SF nanofilms had good biocompatibility. Toluidine blue staining, CCK-8 assay, and EdU/Hoechst33342 staining showed that Gr-SF nanofilms with mass ratio of Gr less than 10% could support the survival and proliferation of co-cultured Schwann cells. Conclusion The Gr-SF nanofilm with mass ratio of Gr less than 10% have proper hydrophilia, conductivity, porosity, and other physical and chemical properties, and have good biocompatibility in vitro. They can be used in tissue engineered nerve preparation.
Objective To observe effect of self-designed drug-loaded nanofilm in preventing postoperative peritoneal cavity adhesion during cholecystectomy in New Zealand white rabbit. Methods The 40 New Zealand white rabbits were randomly divided into blank control group, chitosan group, nanofilm group, and drug-loaded nanofilm group using random number table, the peritoneal cavity adhesions after cholecystectomy at different time (on day 7, 14, 21, and 28) were observed among these 4 groups. Results The adhesion of gallbladder forssa was serious in the blank control group and the adhesion situation had obviously improved among the other three groups, furthermore, the adhesion of the drug-loaded nanofilm group was the slightest. The adhesion score was significantly decreased in the chitosan group, the nanofilm group, or the drug-loaded nanofilm group as compared with the blank control group (P<0.05), which in the drug-loaded nanofilm group was significantly decreased as compared with the chitosan group (P<0.05) or the nanofilm group (P<0.05), which had no significant difference between the chitosan group and the nanofilm group (P>0.05). The nanofilm was degraded on day 14 after surgery and basically completely degraded on day 28 after surgery. The nanofilm degradation points had no significant differences between the nanofilm group and the drug-loaded nanofilm group at different time (P>0.05). Conclusions Drug-loaded nanofilm could prevent postoperative peritoneal cavity adhesion from physical barrier and drug therapy. It provides a new idea for prevention of peritoneal cavity adhesion after general surgery and research and development of new material to prevent peritoneal cavity adhesion in future.